Its a huge development, really. There were several Canadian concessions and a couple smaller American concessions. There's been a lot of ink spilled, and from people who know or care about this a lot more than myself.

The biggest part of this has to be though that the Liberals couldn't do the deal. The Conservatives could, merely through a pleasant relationship with a president in his second term low on political capital. That sends a message that most people won't understand and even fewer will actually appreciate.